Which statement about the axial skeleton is true?

• A. It consists of bones in the limbs
• B. It stores fat in the diaphysis
• C. It consists of the skull, vertebral column, and rib cage
• D. It is not involved in protection of organs

Answer: (C)

The main idea tested is what the axial skeleton includes and what it does. The axial skeleton forms the central axis of the skeleton and its primary role is protection and support of the body's vital organs. It consists of the skull, vertebral column, and rib cage, which together encase the brain, spinal cord, heart, and lungs. That protective, central framework distinguishes it from the appendicular skeleton, which comprises the limbs and girdles. While long bones can store fat in their diaphyses, that feature is a general property of many bones and not what defines the axial skeleton. The axial skeleton does protect organs, so a statement denying that would be incorrect.